Protein fibers trap greenhouse gas

Fibrous protein fragments similar to those in the brains of people with Alzheimer’s disease can pull carbon dioxide out of the air.

Existing methods to capture CO₂ have drawbacks. Some require toxic materials and large amounts of energy; others falter when exposed to water vapor, which fossil fuel combustion releases alongside CO₂.

Because building blocks of proteins bind CO₂ in blood, scientists including David Eisenberg of UCLA exposed protein fibers called amyloids to CO₂ in air, mimicking conditions in a power plant chimney. Each amyloid captured one CO₂ molecule, and the reaction worked even with water vapor present. The fibers released the gas when heated to 100° Celsius, allowing reuse of the amyloids. (To lower atmospheric greenhouse gas levels, CO₂ would need to be stored permanently.)

The fibers do not capture enough CO₂ for industrial use, but they could be improved, the authors write December 23 in the Proceedings of the National Academy of Sciences.